1. Field of the Invention
The present invention relates to a rolling mill drive with axially slidable spindles arranged between the drive shafts and driven rolls, particularly between driven necks of pinions and drive necks of the rolls. The spindle heads of each spindle are each provided with a wobbler with a curved toothing and a coupling sleeve having an internal toothing surrounding the wobbler. The coupling sleeve, in turn, is connected to the pinion neck or the roll neck. The spindle is guided between the coupling sleeves by means of at least one support element arranged in the region of the spindle axis and an axially adjustable pressure plunger.
2. Description of the Related Art
In modern rolling mills it is required to accelerate the rolling work and to increase the rolling accuracy and the rolling speed. In order to compensate any possibly occurring errors in planeness of the rolled material, for example, the work rolls of the rolling mill stand are axially displaced within certain adjustment ranges, so that arching of the strip in the center and at the edges can be advantageously influenced in a controlled manner. For this purpose, a suitable adjusting drive effects the translatory displacement of the work rolls by precisely predetermined distances in the rolling mill stand, while the rotary drive of the work rolls is effected in the known manner by means of spindles which are arranged between the driven work rolls and the driving pinions. Since the pinions are mounted in stationary stands and are in turn connected through suitable gear assemblies to drive motors, the spindles must be constructed in such a way that, on the one hand, they can compensate the displacement of the work rolls in the rolling mills and that, on the other hand, they can transmit the full drive power from the pinions to the work rolls.
For the foregoing reasons, in an older patent application No. P 37 06 557.7, it has been suggested in a spindle of the above-described type to construct the spindle at the end facing the pinion in such a way that the wobbler with the curved toothing is a long sleeve which is slid over a substantial portion of the spindle shaft and wherein the inner surface of the wobbler and the outer surface of the spindle shaft has longitudinally directed toothings which are capable of meshing, for example, a key and groove connection. The length of the toothings is at least such that the entire adjustment distance of the work roll can be compensated.
However, the angular displacement of the spindles is carried out in the known manner in the spindle joint which is formed by the curved toothing of the wobbler and the internal toothing of the coupling sleeve. These structural measures for the longitudinal compensation of the spindle and for adjusting the spindle to the position assumed by the work rolls have been found in practice to be reliable and useful in many situations. However, it was found that great frictional forces in the toothings had to be taken into consideration when the wobbler was displaced on the spindle sleeve.
It is, therefore, the primary object of the present invention to improve the rolling mill drive of the above-described type in several respects. The machine elements for effecting the translatory displacement and for the vertical angular compensation of the spindle are to be structurally simple and simple to manufacture. In addition, the frictional forces to be overcome during displacement of the spindle are to be significantly reduced. Moreover, a problem-free lubrication of the spindle joint and an efficient removal of the frictional heat from the joint are to be ensured.